HI! I've discovered an issue which is pretty much as described in JIRA
OPENJPA-2463. That is, when I have a MappedSuperclass with an @Id, I see this error:
openjpa.Enhance: Error: The identity field defined in the com.yyy.zzz.MyEntity Embeddable is not supported.
This error message is erroneously printed because of the fix via JIRA
OPENJPA-2233. This JIRA was well intended for the case where an @Embeddable contains an @Id (a spec violation) but was too over reaching in that it also flagged an error for a MappedSuperclass with an @Id. I will provide a fix to ensure the error message is only printed when an @Embeddable contains an @Id.